1. Field of the Invention
The present invention relates generally to an image forming apparatus, an image forming method, and a non-transitory computer-readable medium computer-readable recording media.
2. Description of the Related Art
Decorated plates have conventionally been used as interior parts for vehicles such as automobiles and exterior parts for electrical appliances. Generally, interior parts for vehicles and exterior parts for electrical appliances include a base material made of resin and a print layer printed on the base material with ink or the like. In some type of interior parts for vehicles and exterior parts for electrical appliances, the print layer is configured as a light blocking layer.
The above-described interior parts for vehicles and exterior parts for electrical appliances may be manufactured by, for example, printing a light blocking layer (solid opacifying image portion) on a substrate made of resin such as polycarbonate by screen printing. Screen printing is a printing method of making a screen (stencil) where a print image is drawn from print data and applying solvent-based ink, thermal-curing ink, or the like to a substrate through the screen. Screen printing allows printing a light blocking layer in a single printing operation. Because the light blocking layer is required to exhibit a transmission density that prevents light transmission, it is generally necessary to form a thick film in a single printing operation. However, the thickness of a film that can be formed by screen printing is approximately up to 20 to 30 μm. Furthermore, because screen printing is single-color printing, it is necessary to print a plurality of layers using ink of different colors to form a decorative design or the like. This can increase man hours and time taken for processing and undesirably reduce productivity.
Meanwhile, printing techniques include, aside from screen printing, digital printing techniques such as laser-printer electrophotography, thermal transfer printing, and inkjet printing. The digital printing techniques allow directly drawing on a resin substrate without making a screen from print data and therefore are more suitable for small lots. Inkjet printing, which is one of the digital printing techniques, is a technique of performing printing by ejecting ink droplets from electronically-controlled recording head nozzles. Inkjet printing can print an image of a high resolution (i.e., image of high image quality) inexpensively as compared with screen printing by forming a thick film of multiple layers by repeating printing.
Japanese Laid-open Patent Application No. 2012-192721 (Patent Document 1) discloses a method for manufacturing a printed work (which may be a vehicle interior part or an electrical-appliance exterior part), in which a light blocking layer is formed by inkjet printing. The method for manufacturing a printed work disclosed in Patent Document 1 forms a light blocking layer and a light-blocking correction layer by repeatedly performing a step of ejecting droplets of radiation curing ink for forming the light blocking layer and a step of hardening the droplets of the radiation curing ink by irradiating the droplets with radiation.
However, the method for manufacturing a printed work (which may be a vehicle interior part or an electrical-appliance exterior part) disclosed in Patent Document 1 is disadvantageous in that, because multiple layers of a design film exhibiting fine image quality (high image quality) are printed to be laminated on one another, forming the multilayer film is undesirably time consuming and reduces productivity.
Meanwhile, to increase image quality with a conventional inkjet printing technique, it is desired to perform unidirectional printing. Accordingly, forming a multilayer thick film by repeating unidirectional printing is undesirably time consuming and reduces productivity.
Therefore, it is desirable to provide an image forming apparatus, an image forming method, and a non-transitory computer-readable medium capable of reducing the time taken to form an image made of multiple layers while maintaining fine image quality.